Update UsageProgressBarPref icon when device is charging or low battery

- Add new icon for battery low state
 - Update UsageProgressBarPref icon when charging or low battery
 Screenshots:
   https://screenshot.googleplex.com/9HBvV6t6dVsG8eD.png
   https://screenshot.googleplex.com/6TsRu6BTN338FvT.png
   https://screenshot.googleplex.com/nGE29cfsmgKuuaP.png
   https://screenshot.googleplex.com/85NWXSg2PevXAsy.png

Bug: 179237746
Test: make RunSettingsRoboTests -j40
Change-Id: I057874bbf45594c90466cf346b054bf033815dac

res/drawable/ic_battery_low.xml

@@ -0,0 +1,28 @@
+<!--
+  Copyright (C) 2021 The Android Open Source Project
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License
+  -->
+
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+  <path
+      android:fillColor="?android:attr/colorAccent"
+      android:pathData="M12,19m-2,0a2,2 0,1 1,4 0a2,2 0,1 1,-4 0"/>
+  <path
+      android:fillColor="?android:attr/colorAccent"
+      android:pathData="M10,3h4v12h-4z"/>
+</vector>

src/com/android/settings/fuelgauge/BatteryHeaderPreferenceController.java

@@ -21,10 +21,12 @@ import android.app.Activity;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
+import android.graphics.ColorFilter;
 import android.icu.text.NumberFormat;
 import android.os.BatteryManager;
 import android.os.PowerManager;
 import android.text.TextUtils;
+import android.widget.ImageView;
 
 import androidx.annotation.VisibleForTesting;
 import androidx.preference.PreferenceFragmentCompat;
@@ -60,6 +62,7 @@ public class BatteryHeaderPreferenceController extends BasePreferenceController
     private Activity mActivity;
     private PreferenceFragmentCompat mHost;
     private Lifecycle mLifecycle;
+    private ColorFilter mAccentColorFilter;
     private final PowerManager mPowerManager;
 
     public BatteryHeaderPreferenceController(Context context, String key) {
@@ -85,6 +88,9 @@ public class BatteryHeaderPreferenceController extends BasePreferenceController
     public void displayPreference(PreferenceScreen screen) {
         super.displayPreference(screen);
         mBatteryUsageProgressBarPref = screen.findPreference(getPreferenceKey());
+        mAccentColorFilter = com.android.settings.Utils.getAlphaInvariantColorFilterForColor(
+                com.android.settings.Utils.getColorAttrDefaultColor(
+                        mContext, android.R.attr.colorAccent));
 
         if (com.android.settings.Utils.isBatteryPresent(mContext)) {
             quickUpdateHeaderPreference();
@@ -116,13 +122,12 @@ public class BatteryHeaderPreferenceController extends BasePreferenceController
     }
 
     public void updateHeaderPreference(BatteryInfo info) {
-
-        //TODO(b/179237746): Make progress bar widget support battery state icon
-
         mBatteryUsageProgressBarPref.setUsageSummary(
                 formatBatteryPercentageText(info.batteryLevel));
         mBatteryUsageProgressBarPref.setTotalSummary(generateLabel(info));
         mBatteryUsageProgressBarPref.setPercent(info.batteryLevel, BATTERY_MAX_LEVEL);
+        mBatteryUsageProgressBarPref.setCustomContent(
+                getBatteryIcon(!info.discharging, info.batteryLevel));
     }
 
     /**
@@ -139,14 +144,30 @@ public class BatteryHeaderPreferenceController extends BasePreferenceController
         final boolean discharging =
                 batteryBroadcast.getIntExtra(BatteryManager.EXTRA_PLUGGED, -1) == 0;
 
-        //TODO(b/179237746): Make progress bar widget support battery state icon
-
         mBatteryUsageProgressBarPref.setUsageSummary(formatBatteryPercentageText(batteryLevel));
         mBatteryUsageProgressBarPref.setPercent(batteryLevel, BATTERY_MAX_LEVEL);
+        mBatteryUsageProgressBarPref.setCustomContent(getBatteryIcon(!discharging, batteryLevel));
     }
 
     private CharSequence formatBatteryPercentageText(int batteryLevel) {
         return TextUtils.expandTemplate(mContext.getText(R.string.battery_header_title_alternate),
                 NumberFormat.getIntegerInstance().format(batteryLevel));
     }
+
+    //TODO(b/179237746): Update the battery icon after receiving final asset
+    private ImageView getBatteryIcon(boolean isCharging, int batteryLevel) {
+        ImageView batteryIcon = new ImageView(mContext);
+
+        if (batteryLevel <= (mContext.getResources().getInteger(
+                com.android.internal.R.integer.config_lowBatteryWarningLevel))) {
+            batteryIcon.setImageResource(R.drawable.ic_battery_low);
+        } else if (isCharging) {
+            batteryIcon.setColorFilter(mAccentColorFilter);
+            batteryIcon.setImageResource(R.drawable.ic_battery_charging_full);
+        } else {
+            batteryIcon = null;
+        }
+
+        return batteryIcon;
+    }
 }